The present invention relates to delivery systems for fluids. In particular, the invention is directed to a easily assembled and portable system for infusion of fluids such as intravenous solutions, blood plasma or drug solutions at a controlled delivery rate.
Various devices and methods are known for delivery of fluids to a patient. The simplest method utilizes gravity feed from a bag or bottle filled with the fluid suspended above the patient, possibly with a flow restrictor or drip chamber in the tubing connecting the bag to the patient. However, the flow rate can vary depending on many variables such as the height of the fluid bag above the patient, the content of the bag or the tubing or needle size. Also, it is sometimes desirable to deliver the fluids at an accelerated rate or at controlled but nonconstant rate. This can not be readily managed by a gravity feed system.
One of the more complicated methods is to utilize a motor driven pump which is computer controlled and thus is capable of being programmed to deliver fluid at very precise rates. While such devices may be useful at the bed side in a stationary position they are expensive and easily damaged and thus are not preferred for ambulatory use.
Previous attempts to produce a portable device which is resistant to damage and tampering has resulted in expensive and cumbersome products which are not readily controllable. Examples of such devices include inflatable cuffs, pressurized bladders and spring loaded clamps or platforms. However, these devices generally do not offer means for controlling flow.
Thus, there is a need for a simple, portable fluid delivery system which also allows medical personnel to readily control delivery rates of the fluids to the patient.